Minimum age requirements for Dan promotions

Shodan – Ho                15 and up

Shodan 1st Dan           16 

Nidan                            18 
Sandan                         21

Yondan                         25

Godan                           30

Rokudan                       36

Shichidan                     43

Hachidan                      51

Kyudan                          60

Judan                             70